"If one is to foster an understanding and awareness of how the social and the political are not external to technology, then it is important to understand how the technological is in some sense isomorphic to the social and the political
This book - Protocol - consistently makes a case for a material understanding of technology... This type of materialist media studies shows how the question "how does it work?" is also a question "whom does it work for?" In short, the technical specs matter, ontologically and politically."
Think of other physical 'networks' prior to the Internet
Water
Gas
Electricity
Telephone
Cable TV
The amazing thing about the Internet is that you can transmit different kinds of data efficiently. Can your water pipes or gas lines do that?
Why?
The key to having all these different traffic types on the Internet is... that these are all digital data!
What is Unique about the Internet? (compare to other physical networks)
Internet Traffic
Text (e-mail/data)
Image
Audio
Video
The amazing thing about the Internet is that you can transmit different kinds of data efficiently. Can your water pipes or gas lines do that?
Why?
The key to having all these different traffic types on the Internet is... that these are all digital data!
What is the difference between Analog and Digital?
Notes
How is analog analog?
Spinning vinyl under a microscope
Notes
of Audio
7, 9, 11, 12, 13, 14, 15, 14, 13....
Continuous sound wave turned into discrete numbers
Why don't we hear the abrupt transitions?
Text: Movable Type
Notes: From Dani/Kittler "gramophone, film, typewriter"
Atomization of the Phonetic Alphabet into movable type {
- printing press breaks our experience of speech to individuated characters
that may represent any phrase or sentence
- decentralized church power
- set the ground for future technology (photography to the computer) by being
modular, comprising a whole from a fragmented elements.
Moving pictures: 24 frames, pixels
}
Text
Notes
Analog vs Digital
What are the properties of ?
continuous signal
analogous copy of the original signal by transferring the shape of the signal to another medium
noise -> signal loss and distortion (cannot distinguish between error and data)
imperfect copy
xerox copy, casette tapes, LP...?
What are the properties of ?
The internet is designed as a "digital" network.
discrete signal ( 9, 10.2, 12, 14.2, 10.9...etc)
magic of mathematics
noise/error -> error detection/error correction
the sum of all the number I am sending you is X
indefinite faithful copies
if you detect an error, resend!
compression
instead of "0000000000000000000000000000000000000000", you can say something like
"fourty 0s" (much shorter)
Notes
The Digital Network
Computer Networking 1
You digitize audio, video, text...etc
Computer Networking 2
You get a sequence of binary data.
Computer Networking 3
The computer splits the data in smaller chunks and sends out highs/lows on physical cables.
Questions!!
We now know how computers send out signals to the outside world.
Questions we'd like to think about -- what happens when the message enters the "network"
How does it reach its intended destination?
How does snail (physical) mail reach its destination?
How does a phone call reach its destination?
Then, we will discuss how the Internet does it!
Notes
Remember this?
Notes
The Telephone Network
Notes
The Telephone Network 2
Notes
The Telephone Network 3
Notes
The Telephone Network 4
Notes
The Telephone Network 5
Notes
The Telephone Network 6
Notes
The Telephone Network 7
Notes
The Telephone Network 8
What does silence on a telephone network sound like?
Notes
Internet - Packets
One of the radical idea of the Internet was to split the data into smaller chunks called packets.
Internet - Packets
One of the radical idea of the Internet was to split the data into
smaller chunks called packets.
Packet switching, datagrams.
ifconfig -a
size ofpackets: mtu (in bytes)
en0: wired
en1: wireless
fw0: IPover firewire
Internet - Packets 2
%ifconfig -a
to look at MTU (packet) size (byte = 8 bits) and available interfaces
Notes
Like Navigating the NYC Subway w/o a Map
Will not use a map of the subway system
You can ask the conductor at each station for information
Conductor on certain station will know all the station on the line that goes through the station
(eg. conductor on yellow will know all the stations
on yellow line. If the station was a transit station with yellow and red line, the conductor will know all the stations on the yellow and red)
Travel from Midtown station to Broad St station (Brown line)
You are a packet. You know where you are from (SRC) and where you
want to go (DST). You don't have the map of the
Subway(Internet). -> Small window works. Briefly show where Broad
St is. Then move to midtown and ask what they would do.
Some stations, you get off and that is it! Nothing else.
Some stations there are other lines coming in. (Grand Central has the Green line, Purple, Gray).
Routing
Navigating packets to its destination is called "routing"
Imagine the subway system with each line (red, blue, brown...etc)
independently administered. Each line knows about its own
stations and where it connects with other lines.
When nodes under the same administrative domain are connected, they constitute a network
network: connect devices within same organization (= train line)
Routers(=transfer stations).
A router is a special node connected to multiple networks
like a transfer station (Times Square) connected to
multiple lines (Red:1,2,3,9, Yellow:B,D,F,V, Gray:S lines)
A router forwards packets between networks
eg. from network A to network B
Like a transfer station where you can transfer from line 1 to line 2
Any node that has more than two network interfaces can be a router (Just like any train station with more than two lines can be a transfer station).
Notes
Routing 2
(Limited) Scope:
No full map of the internet!!
Routers know a lot about its own network. (eg. router in the Reed network knows where every computer is in its own network).
Routers have limited knowledge outside of its network. (eg. if a packet is going east coast forward it to network B, if it is going to the west coast forward it to network C).
Best-effort:
If one network is down, it will try another route.
If a particular network is congested, routers may forward your packet to another network.
Routers are allowed to drop (erase, give up on) your packets if it's too busy.
Best effort -- no guarantee!!
Looking up routing table using a UNIX command %netstat -r
Routers know a lot - it's kind of like a station in the Yellow
line knowing every station on the yellow line.
The Internet
The Internet is a network of networks, each with different administrative domain
The Reed network is administrated independently of Wikipedia.
Notes
Questions?
What are the strengths/weaknesses of the Internet system as compared from the telephone network?
p11 a telephone network - switching is concentrated and hierarchical. calls go first to a
local office, then on to a regional or national switching office if necessary. each user is connected to only one local office and each local office serves a large number of users. Thus destroying a single local office would cut off many users from the network.
small inexpensive lower quality links and compensate for failures
- message switching to packet switching
Characteristics of the Internet
- Resilient
- No central control
- Best effort
- Small inexpensive lower quality links are welcome and are allowed to fail
- Military Effort (ARPA) in a Cold War environment
- Often mentioned as designed to survive a nuclear attack.
- Resilient against physical attacks. Perhaps not so to virtual/cyber attacks.
Notes
The Internet (Dec. 1969)
What are the questions one could ask through this diagram?
Notes
The Internet (Jun. 1999)
Notes
The Internet (2010)
Notes: find network image of brain, mushroom and others.
The Cloud
from A prehistory of the Cloud (pX)
"situate a network... within the same epistemic space as something that constantly fluctuates and is impossible to know"
A prehistory of the cloud:
"situate a network... within the same epistemic space as something that constantly fluctuates and is impossible to know"
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